Zigzag stitching mechanism



Jan M, 1936 Filed July 26' 1934 V Jan- 14 1-936- c. c. sMlTH l 2027,87

` ZIGZAG STITGIFING MECHANISM Jan. 14, 1936. c. c. SMITH ZIGZAG STITCHING MECHANISM Filed July 26, 1934 5 Sheets-Sheet 4 Filed July 26, 1934 5 Sheets-Sheet 5 Patented Jan. 14, 1936V UNITED STATES PATENT OFFICE ZIGZAG STITCHING M'ECHANISM Clarence C. Smith, Chicago, Ill., assigner to Union Special Machine Company, Chicago, Ill., a cor- The invention relates to new and useful imporation of Illinois Application July 26, 1934, Serial N0. 737,122

6 Claims.

provements in sewing machines, and more particularly to a sewing machine for producing Zigzag stitching.

An object'of the invention is to provide a machine of the parts which above type wherein the rotating impart lateral vibrations to the needle bar are completely housed within the standard of the machine and a housing attached thereto.

r as to leave the space beneath the overhanging arm free and unobstructed.

A still further object of the invention is to provide a machine of the above type wherein the means for reciprocating the needle bar is housed within the standard and the overhanging arm of the machine.

A still further object of the invention is to provide a machine of the above type wherein the lever which reciprocates the needle bar and the transverse sha to the needle ft which imparts lateral vibrations bar are mounted for movement the same axis These and o in their lateral movements. ther objects will in part be obvious and will in part be hereinafter more fully disclosed.

In the drawings- Figure 1 is a view partly in section and partly in front View with parts broken away and parts removed to show more clearly the structure of the machine.

Fig. 2 is a front end view of the machine with the cover plate for the needle head removed.

Fig. 3 is a view partly in rear end elevation and partly in section, and showing the rotating parts which move the needle bar laterally.

Fig. 4 is a View partly in section and partly in plan showing the mechanism beneath the work support'and the mechanism for imparting vibrations to the needle bar.

Fig. 5 is a vi ew partly in top plan and partly in section showing the means for mounting the transverse shaft which moves the needle bar laterally, and the bar.

lever whichreciprocates the .needle Fig. 6 is a view, taken along line 6-6 of Fig. 4, showing the mechanism for operating the loop retainer.

The invention is shown as embodied in a sewing machine which includes a supporting bed I 5 having the usual bearing lugs on which the work support v2 is mounted. Also mounted on Ythe bed is a standard 3, which is hollow. Extending laterally from the standard 3 is an overhanging arm d, which is likewise hollow. At the outer end 10 of the overhanging arm 4 is a needle head 5 in which is mounted a gate 6, and the needle bar 'I is mounted in said gate for reciprocation. The gate 6 is provided with a sleeve 8 at the upper end thereof (see Fig. 5). This sleeve B is mounted 15 for oscillation on a headed bolt 9 which is secured to a bracket I0 by a set screw II. The bracket I Il is attached to the upper end of the needle head by a screw I2.

The needle bar is reciprocated in the supporting -gate 6 therefor by means of a needle operating lever I3 which is connected by a link I4 to a lug I5 secured to the needle bar. This needle operating lever is located in the overhanging arm 4 and is preferably provided with an integral 25 sleeve I6 which is mounted for oscillation on a transverse shaft Il. The needle operating lever I3 is provided with a portion IB integral with the sleeve I6. The portion I8 is connected to an ec centric strap I9 cooperating with an leccentric 30 on the main actuating shaft 2B whereby to oscill-ate the sleeve I6 and reciprocate the needle bar 1. Said main actuating shaft V2l] is mounted for rotation in bearings carried by the bed and is driven by a belt wheel 2|. The gate is oscillated 35 for imparting lateral vibrations to the needle bar so as to Vposition'said needle bar for stitching first at one side and then the other of the central line of the seam for producing zigzag stitching. Said gate is pivotally connected at 22 to a 40 link 23 which in turn is pivoted at 24 to an arm V25 carried by the transverse shaft I'I. `The transverse shaft II is mounted for oscillation in bearings 26 and 2l which are attached to the overhanging arm. Said transverse shaft extends all the way through the overhanging arm and the arm 25 is attached to the front end of this shaft. Mounted on the transverse Vshaft are collars 28 and 29. The sleeve I6 lies between these collars. Said sleeve is free to oscillate on the transverse 5o shaft and the transverse shaft is free to oscillate within the sleeve. In other words, the transverse shaft and the sleeve have 4independent movements.V On the rear end of the transverse shaft I'I is clamped a sleeve 30 carrying an arm 55 3l. This arm 3l at its outer end carries a b-all stud with which a link 32 cooperates. Said link is attached to the ball stud at its upper end, and at its lower end is attached to a ball stud 33 adjustably attached to an arm 34 carried by a shaft 35. Suitable means indicated at 36 is attached to the link 32 for preventing the link from oscillating about its axis duringendwise movement thereof.

The main actuating shaft 29 carries a gear 31 which is located within the standard 3. The standard at the rear side thereof is provided with a slot 38, Attached to the rear face of the standard is a housing 39 which is bolted to the standard by suitable bolts 49, 4S. A cover plate 4I froms a part of the housing 39 and is secured in place by screws 42, 42. Mounted for rotation in bearings in this housing 33 is a shaft 43. Said shaft 43 carries a gear 44 which meshes with the gear 31. A portion 43a of the shaft 43 is eccentrically disposed relative to the point at which the shaft is supported in the housing 39 so that by rotating the shaft slightly in its supporting bearings in the housing 39, the gear 44 may be moved toward and away from the gear 31 in order to obtain a proper meshing of said gears. These gears are so dimensioned that for one rotation of the actuating shaft 2l), said shaft 43 will Ibe given one-half of a rotation, that is, it rotates once for every two rotations of the shaft 20. The

` gear 44 extends through the slot 38 into the standard. The two gears are completely enclosed within the standard, and the housing which is associated therewith. Any lubricating oil -applied to the gears will be retained within the standard and the housing, and there is no chance for any material which is being stitched passing beneath the overhanging arm contacting with said gears.

Mounted on the shaft 43 alongside of the gear `44 is a cam 45. Mounted in a bearing 46 formed as a part of the housing 39 and projecting laterally therefrom, as shown in Figure 4, is the shaft 35. On the inner end of the shaft 35 is a fork 48 which cooperates with the cam 45. When the main actuating shaft rotates, it will impart a rota- .tion to the shaft 43, and the shaft 43, through the cam 45, will impart an oscillation to the shaft `35, and this, through the connecting link 32. will oscillate the transverse shaft I1, and thus it is that the needle gate is shifted back and forth laterally, being moved in one direction for one stitch formation, and then in the other direction for the next stitch formation.

It will be noted from the above that the rotating parts of the train of mechanism which imparts the lateral vibrations to the needle bar are all housed so that no lubricating oil can escape therefrom and contact with the material being stitched. It will also be noted that the oscillating parts which impart lateral movement to the needle bar and which reciprocate the needle bar have their bearings within the overhanging arm or Within the housing, and thus these parts may be efficiently lubricated without any possible chance of the lubricating oil escaping and contacting with the fabric being stitched.

'Ihe needle bar is provided with aneedle 48. Cooperating with the needle beneath the work support is a looper 49. Said looper is mounted on a carrier 59, which in turn is mounted for oscillation on a looper support 5|.k Said carrier is oscillated by a link 49a in the usual manner. The looper support 5l is secured to a rock shaft 52 by a set screw Sie. A collar 52a 4is secured on the shaft 52 and carries an arm 52b which is connected by a link 53 to an eccentric on the main shaft. In this manner the shaft 52 and the looper support 5I are oscillated to give the looper its needle avoiding movements. Associated with the looper is a retainer 54. This retainer is carried by an arm 55 attached to a retainer support 53. The retainer support 56 is mounted on the shaft 52. The retainer support carries a ball stud engaged by a socket 63 which carries a rod 64 which passes through a sleeve`51a on the end of the arm 51 of a bell crank lever and through a sleeve 51b which extends from the body portion of the bell crank lever. The arm 59 of the bell crank lever, which ispivoted at 58, is connected through a suitable link 60 to an eccentric on the main shaft 20. In this manner, the retainer support is moved endwise of the shaft 52. The retainer support 56 is provided with a forked portion Si which cooperates with an eccentric 62 on 'the main shaft 29 whereby the retainer support is oscillated on the shaft 52 and on the same axis as the looper support. This retainer is of a well known character. It moves over the looper and back along the looper for holding the needle thread loop well back on the looper so as to insure the needle entering the thread triangle in the stitch formation. It is particularly adapted for the present machine wherein the needle is vibrated laterally, as it insures there will be a perfect stitch formation in either position of the needle bar. By mounting the retainer so that it moves over the top of the looper, about an axis common `to the looper for its needle avoiding movements, said retainer may be set very close to the looper, and this-does not interfere with the placing of the looper close to the work support.

The material is held on the work support by a presser foot G3 and is moved across the work support by a feed dog 64 which is moved back and forth and up and down in the usual manner.

It is obvious that minor changes in the details of construction and the arrangement of the parts may be made without departing from the spirit of the invention as set forth in the appended claims.

Having thus described the invention, what I claim as new and desire to secure by Letters-Patent, is-

l. A sewing machine including a work support,

an overhanging arm, a main actuating shaft beneath the work support, a needle bar mounted on said overhanging arm for reciprocation and for lateral movement, a transverse shaft mounted on said overhanging arm, means for oscillating said shaft from said main actuating shaft, means connected to said oscillating shaft for moving said needle bar laterally, a needle reciprocating lever mounted on said oscillating shaft for free movement thereon, means for connecting said lever to said needle bar, and means for oscillating said lever from said main actuating shaft.

2. A sewing machine including a work support, an overhanging arm, a main actuating shaft beneath the work support, a needle bar mounted on said overhanging arm for reciprocation and for lateral movement, aV transverse shaft extending through said overhanging arm and mounted for oscillation in bearings carried thereby, a depending Varm carried at the front end of said shaft, a link connected to said depending arm for shifting said needle bar laterally, an arm connected to the rear end of said shaft, means connected to said last-named arm and actuated from said main shaft for oscillating said transverse shaft, a sleeve mounted on said transverse shaft for free 2,027,887 oscillating movement thereon, means for preventing said sleeve from endwise movement, an arm attached to said sleeve and connected to the needle bar for reciprocating the same, an arm attached to said sleeve for oscillating the same, and means connecting the outer end of said lastnamed arm with the actuating member on the actuating shaft.

3. In a sewing machine, a Work support, a standard, an overhanging arm, a needle bar mounted in said overhanging arm for reciprocation and for lateral movement, an actuating shaft located beneath said work support, means mounted in said arm for reciprocating said needle bar from said actuating shaft, means for shifting said needle bar laterally including a gear mounted on said actuating shaft within said standard, said standard having an opening at the rear side thereof, a housing attached to the standard and covering said opening, a shaft mounted in said housing, a gear carried by said shaft and meshing with the gear on the main actuating shaft, a cam on said shaft in the housing, a shaft mounted in a bearing carried by said housing, a forked member attached to said last-named shaft located in said housing and cooperating with said cam, and means whereby the oscillations imparted to said last-named shaft are utilized for Vibrating said needle bar laterally.

4. In a sewing machine, a Work support, a standard, an overhanging arm, a needle bar mounted in said overhanging arm for reciprocation and for lateral movement, an actuating shaft located beneath said work support, means mounted in said arm for reciprocating said needle bar from said actuating shaft, means for shifting said needle bar laterally including a gear mounted on said actuating shaft within said standard, said standard having an opening at the rear side thereof, a housing attached to the standard and covering said opening, a shaft mounted in said housing, a gear carried by said shaft and meshing with the gear on the main actuating shaft, a cam on said shaft in the housing, a shaft mounted in a bearing carried by said housing, a forked member attached to said last-named shaft located in said housing and cooperating with said cam, a transverse shaft carried by said standard, an arm attached to said shaft, a link connecting said arm to an arm on the shaft mounted in the housing whereby the transverse shaft is oscillated from the main actuating shaft, a second arm carried by said transverse shaft, and means operated thereb-y for Vibrating said needle bar laterally.

5. A sewing machine including in combination a work support, a standard, an overhanging arm, a needle bar mounted in said overhanging arm for reciprocation and for lateral movement, a main actuating shaft beneath the work support, said standard having an opening at the rear side thereof, a housing attached to the standard and covering said opening, a shaft mounted in said housing, a gear carried by said shaft, a gear on the main shaft meshing with said first-named gear, said gears being dimensioned so as to inrpart one rotation to the shaft in the housing for two rotations of the main actuating shaft, a cam attached to the shaft mounted in the housing and disposed within said housing, a shaft located in the 'bearing carried by the housing, a forked member carried by said last-named shaft and cooperating with said cam, and means operated by said last-named shaft for vibrating said needle bar laterally.

6. A sewing machine including in combination a work support, a standard, an overhanging arm, a needle bar mounted in said overhanging armfor reciprocation and lateral movement, a main actuating shaft beneath the work support, said standard having a slot in the rear face thereof, a housing attached to said standard and covering said slot, means actuated from said shaft and extending through said standard and overhanging arm for reciprocating said needle bar, means for vibrating said needle bar laterally including a gear on the main actuating shaft located in said standard, a shaft mounted in said housing, a gear carried by said shaft in said housing and extending through said slot in the standard and meshing with the gear on the main actuating shaft, saidgears being dimensioned so that said shaft in the housing is rotated once for two rotations of the main actuating shaft, and devices operated from said shaft in the housing for vibrating said needle laterally.

CLARENCE C. SMITH. 

